to ka, yes I saw that, but I'm trying to make this into a dual band antenna, not just 2 meter. Glenn, I have taken the old antenna apart and cleaned up...boom is around 50 inches, rod stock varies from 25 inches to 4 inches. I think if I just made a 2 meter antenna and added the 440 element it may work, I'm not sure about interaction between the two and also how to drive both. I think the distance between elements will change as I add the 440 elements/driver and even the lengths of the elements may change. That's what I noticed looking at a 2/6 meter converted tv antenna. I would have thought someone had already done this but I find nothing on the web.

Just make sure you put the 2 meter elements on one side of the boom & the 440 mhz elements on the other side so they don't interact with each other.Post some pics of your finished antenna when you are done as well as how well or poorly it's working for you. {:>)

Using numbers from Orr's VHF book I cut a ten element channel 2 Yagiinto a wide spaced two meter beam. I don't have any gain figures but itwas very directive in locating powerline RFI. I made a 115 mile contact ontwo meters AM with it using a converted taxicab base transmitter and AMECOnuvistor converter.

The original TV antennas are designed to work on two bands (Channels 2-6 and7 - 13) where one is (roughly) the third harmonic of the other. If you take thecurrent dimensions of the antennas and assume it is designed for 63 and 190 MHz,then you can divide all the element lengths and spacings by 146 / 63 = ~2.3and you should have a usable antenna. That doesn't mean it will be optimized,but it should work. (The short elements - less than a foot or so - are for UHF,and don't need to be included in the later design.)

A better design would be optimized for a smaller frequency range, such as140 - 150 MHz, rather than 129 - 195 (which is what just scaling the originalantenna would give you.) Someday I'd like to have the time to develop sucha design: there may be some around if you look hard enough.

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